I acquired a used 2005 R1200GS from a friend of mine. Dead battery, bike had been sitting more or less last couple years. After installing new battery, upon test ride, I noted the rear servo wasn't working and rear brake was in residual braking mode. After doing a brake flush of the wheel circuits and ABS controller, the rear servo still didn't work. I purchased a GS911 tool and found the following code: 24951: ABS motor rear, defective; currently present. Reset code and again found it replicated upon second test.
I ended up finding a used ABS module from a donor bike (2006 1200RT). Removed original ABS control module from GS and installed this replacement. After bleeding procedure, servo runs continuously when key turned on. Front actuates servo when lever depressed, but rear does not actuate servo (same as problem on old unit). I read the codes on new unit, which included 25193: Brake fluid level low, not present now; and 24145: Internal Control Module error - unpermissible vehicle coding found - the fault is currently present.
Battery is at about 12.8V, F&R micro switches appear to be working (clicking, and actuating brake light), bleeding wheel circuits seemed to go pretty well, and F&R ABS pump reservoirs have appropriate level of fluid. I can't say for sure there isn't air in the system, but I bled it as best I could. I couldn't get the rear servo to pump fluid out of the rear caliper (it does not actuate when I depress the rear petal). Also, when the GS911 is connected to the bike and my PC, the servo continues running even after turning the key off until I quickly pulled the negative battery cable.
Wondering a few things and looking for insight from anyone who has had similar experience:
I am thinking going through the bleed procedure again just to see if any more air is in the system and can be removed to try and increase the odds that this is not causing any issues. After all, the system was opened up to change out the old ABS module.
Could the need to re-code the new to this bike/ used ABS control module be causing this issue? Can I reprogram this with the GS911 tool or another means, or does this require a trip to the dealer to hook up to their diagnostic system?
If whatever unidentified issue which caused the original ABS rear servo failure (happened when the original owner had it, before my possession) is still not fixed, could this be causing the servo to continuously run? I was thinking that maybe some issue caused the servo to run continuously until it ceased to work anymore. Any thoughts on what may cause this? I have looked over the wiring somewhat to try and see if I found any bad spots, but didn't turn up anything. Could have missed something, though. I also changed the FD fluid and cleaned the speedo/ABS sensor.
Any help is appreciated. Thanks.